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Part CCSIR NET June 2024the-jump-condition-fixes-the-sign

The jump condition fixes the sign

Consider the boundary value problem (BVP) (e^(−5x)y′)′ + 6e^(−5x)y = −f(x), 0 < x < ln 2, with y(0) = 0, y(ln 2) = 0. If G(x,ξ)=(e(3x)+G(x, \xi) = (e^(3x) + Be^(2x))(Ce(2ξ)+^(2\xi) + De(3ξ))^(3\xi)) for 0≤ξ≤x0 \le \xi \le x, and G(x,ξ)=(e(3ξ)+G(x, \xi) = (e^(3\xi) + Be(2ξ))(^(2\xi))(Ce^(2x) + De^(3x)) for x≤ξ≤ln⁡2(x \le \xi \le \ln 2 (Green's function) is such that ∫0(ln⁡2)G(x,ξ)f(ξ)dξ\int_{0}^(\ln 2) G(x, \xi)f(\xi)d\xi is the solution of the BVP, then the values of B, C and D are

  1. A.B = −2, C = −1, D = 1
  2. B.B = −2, C = 1, D = −1✓ Correct
  3. C.B = 2, C = 1, D = 1
  4. D.B = 2, C = −1, D = −1

You have the answer. Trap Analysis is why the other three were written.

Not a worked solution repeated four times — the specific reasoning error each wrong option was built to reward, and why this one tests execution slip.

See pricing

50 are analysed free — try those first.

The trap it tests

Execution slip

The idea was right. The computation was not.

Drill statements like this

Related counterexample: Every boundary value problem has a Green's function

More on this topic

The chapter behind this: Sturm–Liouville problems and Green's functions — free to read

From Ordinary Differential Equations › Sturm–Liouville problems and Green's functions

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